Toxicity of mercury

Abstract

A ruling by the European Union heralds the demise of those useful clinical instruments, the mercury thermometer and the mercury sphygmomanometer. The new laws have been passed because of worries about mercury poisoning. Yet you can drink metallic mercury and come to no harm. What does it all mean? There are three forms of mercury from a toxicological point of view: inorganic mercury salts; organic mercury compounds; and metallic mercury. Inorganic mercury salts are water soluble, irritate the gut, and cause severe kidney damage. Organic mercury compounds, which are fat soluble, can cross the blood brain barrier and cause neurological damage. Mercury metal poses two dangers. It can be vaporised: the vapour pressure at room temperature is about 100 times the safe amount, so Keywords: mercury; toxicity; thermometer; sphygmomanometer Toxicity of mercuryA new European Union directive 1 will prohibit the use of mercury in sphygmomanometers and clinical thermometers. We review here the toxic effect of mercury and its compounds and discuss their relevance to the environment and to modern medicine.The Chinese used mercury (II) sulphide 1000 years before the birth of Christ as the red dye pigment vermilion. It was used similarly in the GraecoRoman world, with both Hippocrates and Galen recording its toxic effects. Since then its toxicity has become well known in metalworkers, miners, felthat manufacturers, dyers and paint manufacturers. Despite this, mercury has been incorporated into the treatment of man's maladies from ancient times. Its main use has been to treat syphilis, from its first appearance in the West in the 15th century up to World War II. 2 Mercury and its salts have at various times been used as antiseptics, skin ointments, laxatives, diuretics, bowel washouts for the treatment of colorectal cancer, and scabicides. It is still used today as a solvent for the silver-tin amalgams used in dental fillings. So how toxic is mercury? The hazards of mercuryThere are substantial differences in toxicity of elemental mercury metal, inorganic mercury salts, poisoning can occur if mercury metal is spilled into crevices or cracks in the floorboards. Dentists are occasionally poisoned this way. Mercury easily crosses into the brain, and causes tremor, depression, and behavioural disturbances. A second danger from metallic mercury is that it is biotransformed into organic mercury, by bacteria at the bottom of lakes. This can be passed along the food chain and eventually to man. It was this process that led to the Japanese tragedy at Minimata Bay in the late 1950s when over 800 people were poisoned. It is the need to reduce mercury contamination of the environment which should encourage us to cut the usage of metallic mercury. However, much more metallic mercury is spilled as waste by the chemical industry than is dropped on the floor in the clinic.

Development and validation of a blinded hybrid device according to the European Hypertension Society protocol: Nissei DM-3000

“…[2][3][4] It has distinct advantages in sub-populations in which automated oscillometric device readings are less accurate, particularly for those with conditions such as diabetes, 5 arrhythmias, 6 pre-eclampsia 7 and for the elderly. 8 Since its proposal in 2001, various hybrid devices 9,10 have been manufactured and validated.…”

Effects of Eriobotrya japonica (Lindl.) flower extracts on mercuric chloride-induced hepatotoxicity in rats

“…Thus, they are more readily absorbed by the gastrointestinal tract. Since the liver is the body detoxification center, Hg can cause damages in it [1]. Mercury (II) is a potential hepatotoxic agent and oxidative stress is its major cause [2].…”

Evaluation of the A&D UA-767 and Welch Allyn Spot Vital Signs noninvasive blood pressure monitors using a blood pressure simulator

“…However, the mercury sphygmomanometer has been replaced in many locations by other devices because of the health hazards associated with the use of mercury. 1 Oscillometric noninvasive blood pressure (NIBP) monitors are a popular choice as, unlike auscultatory blood pressure monitors, they do not require the identification of Korotkoff sounds in order to make the measurement. Some of these devices are sufficiently inexpensive to be regarded as not cost effective to repair, whereas the converse is true of others.…”